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241.
Erika Margarita Carrillo-Casas Zaydy Suástegui-Urquijo Sara Arroyo-Escalante Rosario Morales-Espinosa David Moncada-Barrón Lorena Hernández-Delgado José Luis Méndez-Sánchez Gabriela Delgado-Sapién Armando Navarro-Ocaña Ángel Manjarrez-Hernández Juan Xicohtencatl-Cortes Rigoberto Hernández-Castro 《Folia microbiologica》2013,58(3):229-234
Nosocomial infections are a major cause of morbidity and mortality among neonates admitted to neonatal intensive care units (NICUs). The aim of this paper was to describe an outbreak of Escherichia coli among infants admitted to the NICU of the General Hospital “Dr. Manuel Gea Gonzalez” in May of 2008. The isolated E. coli strains were identified using standard biochemical methods. The susceptibilities of these strains were analysed by determining their minimal inhibitory concentrations. Following this, their molecular relationships to each other were assessed by pulsed field gel electrophoresis (PFGE) analysis and corroborated by serology. Twelve E. coli strains were isolated from blood, urine, or indwelling catheter samples from five cases of preterm infants within a 3-day period. Patients were admitted to the NICU of the general hospital and, during the outbreak, developed sepsis caused by E. coli. For four of the patients, the average age was 23 days, while one patient was a 3-month-old infant. Prior to sepsis, the infants had received assisted ventilation and hyperalimentation through a central venous catheter. Two profiles were observed by PFGE; profile A was identified as the outbreak’s cause and an outcome of cross-infection, while profile B showed genetic differences but serologically it was identified as part of the same serotype. We conclude that E. coli colonised the patients through horizontal transmission. A focal source of the microorganism in this outbreak was not identified, but cross-transmission through handling was the most probable route. 相似文献
242.
Pollen morphology of 58 species from 17 putative genera of the tribe Atripliceae (Chenopodiaceae) was investigated using light (LM) and scanning electron microscopy (SEM). Morphological variation was analyzed based on a dense sampling of the subtribes Atriplicinae and Eurotiinae, including many of the species in the two largest genera: Atriplex and Obione. The pantoporate pollen grains of Atripliceae are characterized by their spheroidal or subspheroidal shape, flat or moderately vaulted mesoporia with 21–120 pores, tectum with 1–8 spinules and 5–28(?38) puncta per?µm2, and 1–13 ectexinous bodies bearing 1–7 spinules each. Taxonomic relevance of the most important pollen morphological characters is discussed (pollen diameter, pore number, pore diameter, interporal distance, spinule and puncta density and ratio, number of ectexinous bodies, and their spinules). Pollen morphological data support the exclusion of Suckleya from the tribe and the recognition of subtribe Eurotiinae, but suggest that it needs to be reviewed. Pollen does not support generic recognition of Atriplex, Neopreissia and Obione and infrageneric subdivisions as currently recognized, and suggests the need to review them. Smaller or monotypic genera, such as Axyris, Ceratocarpus, Endolepis, Krascheninnikovia, Microgynoecium, Proatriplex and Spinacia have distinctive pollen morphological characters that support their generic status. Grayia needs to be reevaluated; although its two species are distinct from all the other species in the study, there are notable differences between each of them, and this suggests they may not form a natural group. Multivariate techniques were employed to investigate if there are discrete patterns of variation within Atripliceae. Principal Component Analyses (PCA) weakly differentiates four groups based on variation in pore number, puncta density per?µm2, and ratio between spinule and puncta density per?µm2; species of Ceratocarpus, Haloxanthium, Krascheninnikovia, Manochlamys, Microgynoecium, Spinacia, and some species of Atriplex and Obione are isolated. Preliminary results indicate that pollen data are potentially useful in the classification of the tribe, and further studies will be of taxonomic value. 相似文献
243.
Andrew R. Williams Sara E. Zakutansky Kazutoyo Miura Matthew D.J. Dicks Thomas S. Churcher Kerry E. Jewell Aisling M. Vaughan Alison V. Turner Melissa C. Kapulu Kristin Michel Carole A. Long Robert E. Sinden Adrian V.S. Hill Simon J. Draper Sumi Biswas 《International journal for parasitology》2013
The mosquito innate immune response is able to clear the majority of Plasmodium parasites. This immune clearance is controlled by a number of regulatory molecules including serine protease inhibitors (serpins). To determine whether such molecules could represent a novel target for a malaria transmission-blocking vaccine, we vaccinated mice with Anopheles gambiae serpin-2. Antibodies against Anopheles gambiae serpin-2 significantly reduced the infection of a heterologous Anopheles species (Anopheles stephensi) by Plasmodium berghei, however this effect was not observed with Plasmodium falciparum. Therefore, this approach of targeting regulatory molecules of the mosquito immune system may represent a novel approach to transmission-blocking malaria vaccines. 相似文献
244.
Aaron L. Smith Sara M. Freeman Ronald J. Voll Larry J. Young Mark M. Goodman 《Bioorganic & medicinal chemistry letters》2013,23(19):5415-5420
The compound 1-(1-(2-(2-(2-fluoroethoxy)-4-(piperidin-4-yloxy)phenyl)acetyl)piperidin-4-yl)-3,4-dihydroquinolin-2(1H)-one (1) was synthesized and positively evaluated in vitro for high potency and selectivity with human oxytocin receptors. The positron emitting analogue, [F-18]1, was synthesized and investigated in vivo via PET imaging using rat and cynomolgus monkey models. PET imaging studies in female Sprague–Dawley rats suggested [F-18]1 reached the brain and accumulated in various regions of the brain, but washed out too rapidly for adequate quantification and localization. In vivo PET imaging studies in a male cynomolgus monkey suggested [F-18]1 had limited brain penetration while specific uptake of radioactivity significantly accumulated within the vasculature of the cerebral ventricles in areas representative of the choroid plexus. 相似文献
245.
Miriam Andrés Mónica Bravo Maria Antonia Buil Marta Calbet Jordi Castro Teresa Domènech Peter Eichhorn Manel Ferrer Elena Gómez Martin D. Lehner Imma Moreno Richard S. Roberts Sara Sevilla 《Bioorganic & medicinal chemistry letters》2013,23(11):3349-3353
High throughput screening identified the pyrazole-4-acetic acid substructure as CRTh2 receptor antagonists. Optimisation of the compounds uncovered a tight SAR but also identified some low nanomolar inhibitors. 相似文献
246.
Sara D. Leonhardt Claus Rasmussen Thomas Schmitt 《Proceedings. Biological sciences / The Royal Society》2013,280(1762)
Chemical compounds are highly important in the ecology of animals. In social insects, compounds on the body surface represent a particularly interesting trait, because they comprise different compound classes that are involved in different functions, such as communication, recognition and protection, all of which can be differentially affected by evolutionary processes. Here, we investigate the widely unknown and possibly antagonistic influence of phylogenetic and environmental factors on the composition of the cuticular chemistry of tropical stingless bees. We chose stingless bees because some species are unique in expressing not only self-produced compounds, but also compounds that are taken up from the environment. By relating the cuticular chemistry of 40 bee species from all over the world to their molecular phylogeny and geographical occurrence, we found that distribution patterns of different groups of compounds were differentially affected by genetic relatedness and biogeography. The ability to acquire environmental compounds was, for example, highly correlated with the bees'' phylogeny and predominated in evolutionarily derived species. Owing to the presence of environmentally derived compounds, those species further expressed a higher chemical and thus functional diversity. In Old World species, chemical similarity of both environmentally derived and self-produced compounds was particularly high among sympatric species, even when they were less related to each other than to allopatric species, revealing a strong environmental effect even on largely genetically determined compounds. Thus, our findings do not only reveal an unexpectedly strong influence of the environment on the cuticular chemistry of stingless bees, but also demonstrate that even within one morphological trait (an insect''s cuticular profile), different components (compound classes) can be differentially affected by different drivers (relatedness and biogeography), depending on the functional context. 相似文献
247.
248.
Claudio Battilocchio Giovanna Poce Salvatore Alfonso Giulio Cesare Porretta Sara Consalvi Lidia Sautebin Simona Pace Antonietta Rossi Carla Ghelardini Lorenzo Di Cesare Mannelli Silvia Schenone Antonio Giordani Luigia Di Francesco Paola Patrignani Mariangela Biava 《Bioorganic & medicinal chemistry》2013,21(13):3695-3701
We report the synthesis and bio-pharmacological evaluation of a class of pyrrole derivatives featuring a small appendage fragment (carbaldehyde, oxime, nitrile) on the central core. Compound 1c proved to be extremely effective in vivo, showing an interesting anti-nociceptic profile that is comparable to reference compounds already marketed, hence representing a great stimulus for a further improvement of this class of molecules. 相似文献
249.
The molecular phylogeny of the genus Odontobuthus Vachon, 1950 (Scorpiones: Buthidae) in Iran was evaluated using two mitochondrial DNA genes, cytochrome c oxidase, subunit I (COI) and 16S ribosomal RNA (16S rRNA). The molecular phylogenetic analyses were performed using Maximum Parsimony, Maximum Likelihood and Bayesian inference methods. The resulting topologies supported two main clades: the clade comprising Odontobuthus doriae, O. bidentatus, and O. tavighiae, and another one which is the O. tirgari clade. The results clearly presented additional support for the taxonomic validity of the recently described species, O. tirgari and O. tavighiae. In addition, the monophyly of two previously described species O. doriae and O. bidentatus was confirmed. According to the data presented here, three taxonomically valid species belonging to the genus Odontobuthus occur in Iran. 相似文献